Receiving apparatus, receiving methods, and name resolving method

ABSTRACT

At step S 1,  a URI of a desired content is input. At step S 3,  corresponding to the input URI, a proper resolution executing portion is selected. A plurality of resolution executing portions perform processes in parallel. At step S 4,  with reference to a correlation table that correlates identification names of contents and file names in a storing unit, a name resolving process is performed. At step S 6,  with reference to name resolution table data transmitted as an MPEG2 section table in a satellite broadcast, a name resolving process is performed. At step S 8,  by communicating with a name resolving service on a network such as DNS, a name resolving process is performed. After the name resolving processes in all methods have been completed, at step S 10,  an acquired location list L is sent to a content acquiring portion. The content acquiring portion references the list L and acquires a content designated by the URI.

TECHNICAL FIELD

The present invention relates to a receiving apparatus, a receivingmethod, and a name resolving method used in the technical field of forexample data distribution.

BACKGROUND ART

Currently, on the Internet, information/data (content) described in HTML(Hypertext Markup Language)/XML (extensible Markup Language) isdistributed. As a procedure for acquiring data on the Internet, the userinputs a URI (Uniform Resource Identification name) (or URL (UniformResource Locator), this notation is applied in the followingdescription)) that identifies his or her desired content on a clientunit. A content corresponding to the input URI is transmitted from a webserver. The URI/URL is a standard notation used to reference datadistributed on WWW (World Wide Web).

In a conventional data distributing system using the Internet, toconvert an input URI into a content or to interpret an input URI as acontent, a DNS (Domain Name System) and a web server perform a nameresolving process for the content. The name resolving process normallystands for a process for translating a domain name into an IP address orvice versa. However, in this specification, the name resolving processstands for a process for converting an identifier into a physicallocation of a content or interpreting an identifier as a physicallocation of a content.

In future, it is expected that a data broadcasting system will beestablished and various types of contents such as program informationand program advertisement information will be distributed through abroadcasting network. To reference and identify data that is distributedby such a data broadcasting system, it is preferred to reference themwith the URI format that is used in HTML documents or the like of theInternet. However, it is difficult to interpret an URI and reference acorresponding content on a broadcasting network using the same nameresolving system, which uses a DNS and a web server as a conventionalweb. Generally, a name resolving system dedicated for a URI of a contenton a broadcasting network is used.

In future, when the Internet and the broadcasting network will befurther unified, it can be predicted that a content uniquely identifiedby a particular URI is distributed on the Internet and a plurality ofdigital broadcasting networks. From this point of view, it is necessaryto unify the URI name resolving system for the Internet and the URI nameresolving system for digital broadcasting network.

Therefore, an object of the present invention is to provide a receivingapparatus, a receiving method, and a name resolving method that allowdifferent content name resolving systems used on various networks to beunified.

DISCLOSURE OF THE INVENTION

To solve the forgoing problem, in one embodiment the present inventionis a receiving apparatus for receiving data as a content to be provided,comprising:

-   -   a receiving means for receiving data;    -   a content storing means for storing data as a content received        by the receiving means;    -   an identifier identifying means for identifying an identifier of        a desired content;    -   a name resolving means for interpreting the identified        identifier and identifying the location of the content;    -   a content acquiring means for acquiring a content from the        location identified by the name resolving means;    -   a means for causing the content acquiring means to acquire a        content; and

a reproducing means for reproducing a content acquired by the contentacquiring means.

In another embodiment the present invention is a receiving method forreceiving data as a content to be provided, comprising the steps of:

-   -   receiving data and storing the received content data;    -   identifying an identifier of a desired content;    -   interpreting the identified identifier and identifying the        location of the content;    -   acquiring a content from the location identified at the name        resolving step; and    -   reproducing the acquired content.

In an additional embodiment the present invention is a name resolvingmethod, comprising the steps of:

-   -   identifying an identifier of a desired content;    -   interpreting the identified identifier; and    -   identifying the location of the content,    -   wherein the name resolving method includes a name resolution        executing method, and    -   wherein the name resolution executing method is performed by        referencing a correlation table that correlates identifiers and        locations of contents.

According to the present invention, since there are an identifieridentifying means and a name resolving means, content name resolvingsystems on a plurality of networks can be unified. In addition,according to the present invention, since name resolution table that istransmitted from the outside and an external name resolution table canbe referenced, a new name resolving means can be easily extensibly used.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram showing the structure of a content providingsystem according to an embodiment of the present invention;

FIG. 2 is a block diagram showing the structure of an example of abroadcasting station according to an embodiment of the presentinvention;

FIG. 3 is a block diagram showing the structure of an example of areceiving apparatus according to the embodiment of the presentinvention;

FIG. 4 is a schematic diagram showing the structure of an example of aname resolving portion of the receiving apparatus;

FIG. 5 is a flow chart showing a name resolving procedure;

FIG. 6 is a schematic diagram showing an example of a correlation tableof URIs and content locations; and

FIG. 7 is a schematic diagram for explaining a name resolving process ofthe content providing system.

BEST MODES FOR CARRYING OUT THE INVENTION

Next, with reference to the accompanying drawings, an embodiment of thepresent invention will be described. FIG. 1 shows an example of acontent providing system according to the embodiment of the presentinvention. Information providing units 101 ₁ and 101 ₂ store contentdata that they provide in their server units. An example of content datais a WWW (World Wide Web) page described in XML or HTML. The informationproviding units 101 ₁ and 101 ₂ are connected to a broadcasting station102 and receiving apparatuses 103 ₁ and 103 ₂ through a bi-directionalnetwork 105.

The broadcasting station 102 stores content data that it provides in itsserver unit. The broadcasting station 102 is connected to the receivingapparatuses 103 ₁ and 103 ₂ through a multi-cast network 104. As aresult, the broadcasting station 102 provides content data to thereceiving apparatuses 103 ₁ and 103 ₂. In addition, the broadcastingstation 102 receives content data from the information providing units101 ₁ and 101 ₂ through the bi-directional network 105 or a dedicatedline and provides the received content data to the receiving apparatuses103 ₁ and 103 ₂ through the multi-cast network 104. A real example ofthe multi-cast network is a broadcast (a digital broadcast such as asatellite broadcast or a ground wave broadcast).

The receiving apparatuses 103 ₁ and 103 ₂ receive and store contents andprovide them to their users. Information of contents is transmitted toand stored in the receiving apparatuses 103 ₁ and 103 ₂ through themulti-cast network 104. Alternatively, information of contents istransmitted to the receiving apparatuses 103 ₁ and 103 ₂ through thebi-directional network 105.

FIG. 2 shows an example of the structure of the broadcasting station102. A content operating portion 201 inputs a content. The input contentis stored in a content storing portion 202. Each of contents stored inthe content storing portion 202 is assigned a unique identificationname. The identification names and information of locations of contents(this information is referred to as content location information) arestored in a name registering portion 204. The content locationinformation is for example a file name of a content stored in thecontent storing portion 202 or a network address of a server that storesa content. When a content is broadcast, the content location informationis for example information that designates a stream that is broadcast.

A content stored in the content storing portion 202 is transmitted tothe receiving apparatuses 103 ₁ and 103 ₂ through a transmitting portion203 and the multi-cast network 104. In addition, corresponding torequests from the receiving apparatuses 103 ₁ and 103 ₂, contents may betransmitted to the receiving apparatuses 103 ₁ and 103 ₂ through acommunication controlling portion 205 and the bi-directional network105.

As with a content, an identifier thereof and content locationinformation stored in the name registering portion 204 are transmittedto the receiving apparatuses 103 ₁ and 103 ₂ through the transmittingportion 203 and the multi-cast network 104. In addition, when thereceiving apparatuses 103 ₁ and 103 ₂ inquires for name resolvingprocesses, corresponding to information of the name registering portion204, the inquired content location information can be replied to thereceiving apparatuses 103 ₁ and 103 ₂ through the communicationcontrolling portion 205 and the bi-directional network 105.

The structure of each of the information providing units 101 ₁ and 101 ₂is the same as the structure of the broadcasting station 102 except thateach of the information providing units 101 ₁ and 101 ₂ does not containthe transmitting portion 203 shown in FIG. 2.

FIG. 3 shows an example of the structure of the receiving apparatus 103₁. A receiving portion 306 receives a content through the multi-castnetwork 104 and stores the received content to a content storing portion303. Alternatively, a communication controlling portion 307 receives acontent through a bi-directional network on demand. The communicationcontrolling portion 307 stores the received content to the contentstoring portion 303.

The user inputs an identification name of a desired content with aninput portion 301. A name resolving portion 302 interprets an identifierof the input content and passes location information for the content toa content acquiring portion 304. The content acquiring portion 304actually acquires a content corresponding to the received contentlocation information passed from the name resolving portion 302.

To acquire a content through the multi-cast network 104, the receivingportion 306 is controlled by the content acquiring portion 304.Likewise, to acquire a content through the bi-directional network 105,the communication controlling portion 307 is controlled by the contentacquiring portion 304. Normally, the acquired content is temporarilystored in the content storing portion 303. A content acquired throughthe content acquiring portion 304 is displayed on a content displayingportion 305.

FIG. 4 shows a detailed structure of an example of the name resolvingportion 302 of each of the information providing units 101 ₁ and 101 ₂.An identification name of a content that is input from the input portion301 is converted into content location information by a name resolvingprocess. There are various name resolution processing protocols forcontents on the Internet, for contents on broadcasting networks, and forcontents in storing/recording units of receiving apparatuses.

For a content on the Internet, a name resolving system, for example, aconventional DNS is used. For a content on a digital broadcast, a nameresolving system that references a name resolution table that isbroadcast along with the content is used. For a content in astoring/recording unit of a receiving apparatus, a name resolving systemthat references a correlation table that correlates identification namesof contents and file names in the storing unit is used.

Besides a difference in name resolving protocols corresponding tonetwork types, there is a possibility of which there is a difference inname resolving protocols corresponding to name managing organizations.For example, when a name resolving process for an identifier assigned bya system of a particular name managing organization is performed, it maybe necessary to be connected to a special name resolving system.

The name resolving portion 302 causes a plurality of resolutionexecuting portions 402, 403, and 404 to execute a plurality of differentname resolving protocols. The resolution executing portion 402references a correlation table that correlates identification names ofcontents and file names in the storing unit and performs a nameresolving process. In contrast, the resolution executing portion 403references a name resolution table broadcast along with a content in thereceiving portion 306 and performs a name resolving process. Theresolution executing portion 404 communicates with an external nameresolving system through the communication controlling portion 307 andthe bi-directional network 105 and performs a name resolving process. Aname resolution selecting portion 401 selects a proper resolutionexecuting portion corresponding to an identifier that is input from theinput portion 301. The selected resolution executing portion performs aname resolving process.

Alternatively, when programs of the resolution executing portions 402,403, and 403 are downloaded through a network, a new name resolvingprotocol can be used. The resolved content location information is sentto the content acquiring portion 304 (a plurality of types of contentlocation information may be sometimes sent).

FIG. 5 is a flow chart showing a name resolving process. At step S1, anidentification name URI of a desired content is input with the inputportion 301. At step S2, a content location list L is initialized. Atstep S3, with reference to the input URI, the name resolution selectingportion 401 selects a proper resolution executing portion from theresolution executing portions 402, 403, and 404. When a URI has aspecial format, a predetermined resolution executing portion performs acorresponding name resolving process. Since one content may bedistributed on various networks, unless a resolution executing portionis selected corresponding to the format of the URI or the like, theresolution executing portions 402, 403, and 404 perform respective nameresolving processes.

FIG. 5 shows processes that the resolution executing portions 402, 403,and 404 perform in parallel. In other words, the resolution executingportion 402 performs processes of steps S4 and S5. The resolutionexecuting portion 403 performs processes of steps S6 and S7. Theresolution executing portion 404 performs processes of steps S8 and S9.Alternatively, these resolution executing portions may successivelyperform their processes.

At step S4, the resolution executing portion 402 references acorrelation table that correlates identifier names of contents and filenames in a storing unit (for example, the content storing portion 303)and performs a name resolving process. At step S5, the resolutionexecuting portion 402 adds location information corresponding to theinput URI to the list L in the content storing portion 303. At step S6,the resolution executing portion 403 references name resolution tabledata transmitted as an MPEG2 section table in a satellite broadcast andperforms a name resolving process. At step S7, the resolution executingportion 403 adds location information corresponding to the input URI tothe list L. At step S8, the resolution executing portion 404communicates with a name resolving service such as DNS on a network andperforms a name resolving process. At step S5, the resolution executingportion 404 adds location information corresponding to the input URI tothe list L. After the name resolving processes in all the methods havebeen completed, at step S10, the obtained location list L is sent to thecontent acquiring portion 304. The content acquiring portion 304references the location list L and acquires a content designated by theURI.

FIG. 6 shows some examples of tables that correlate URIs and locationinformation (locators). In FIG. 6A, reference numeral 601 represents acorrelation table that correlates identification names and names ofcontents (file names) in the case that the contents have been stored ina storing unit of the receiving apparatus (for example, the contentstoring portion 303). The receiving apparatus manages the correlationtable 601. The name resolution executing portion 402 references thecorrelation table 601, extracts a locator (file name) corresponding tothe URI to be resolved, and supplies the extracted file name to thecontent acquiring portion 304.

In FIG. 6B, reference numeral 602 represents a correlation table thatcorrelates identification names and location information (channels) thatdesignates broadcast streams. The information providing units 101 ₁ and101 ₂ on the transmission side or the broadcasting station 102 transmitsthe correlation table 602 in the format of for example MPEG2 sectiontable. The receiving apparatus has received the correlation table 602.The name resolution executing portion 403 references the correlationtable 602, extracts a locator corresponding to the URI to be resolved,and supplies the extracted locator to the content acquiring portion 304.The content acquiring portion 304 accesses a stream corresponding to thelocator and acquires the content.

In FIG. 6C, reference numeral 603 represents a correlation table thatcorrelates identification names and locations of content servers(addresses of servers and so forth) on the Internet in the case that thecontents are stored in the servers on the Internet. A name resolvingserver on a network has such a correlation table 603. When theresolution executing portion 404 performs a name resolving process, theresolution executing portion 404 inquires the name resolving server fora locator corresponding to a URI and extracts the locator therefrom.

FIG. 7 schematically shows a name resolving system. As an example, acontent 604 with an identifier name (uri://abc/ghi.mpg) is present inthe content storing portion 303 of a receiving apparatus 701, a databroadcast 702, and a web server 703 on the Internet. Locationinformation that represents the location of the content 604 is describedin the correlation tables 601, 602, and 603. The resolution executingportions 402, 403, and 404 perform the following name resolvingprocesses for designating the location of the content 604.

The resolution executing portion 402 references the correlation table601, which correlates identification names of contents and file names inthe storing unit, and determines whether or not the content storingportion 303 has stored the content corresponding to the input URI. Inthe example of the correlation table 601 shown in FIG. 6A, the input URIhas been stored. The locator is (file://abcdefghi.mpg).

As with a content, the resolution executing portion 403 references thecorrelation table 602 such as an MPEG-2 section table that istransmitted from a broadcasting station and performs a name resolvingprocess. In the example shown in FIG. 6B, the locator corresponding tothe input URI is (dvb://123.256.789; 111@2000-07-08T00:00:00D120).

The resolution executing portion 404 communicates with a name resolvingservice (a server that has the correlation table 603, which correlatesnames and locations, for example, a DNS server 704) on a network throughthe communication controlling portion 307 on demand and performs a nameresolving process. In the example shown in FIG. 6C, the locatorcorresponding to the input URI is (http://192.168.0.1/def/ghi.mpg). Theresolution executing portion 404 accesses a web server 703 representedby the locator and acquires the content.

It should be noted that the present invention is not limited to theforgoing embodiment. In other words, without departing from the sprit ofthe present invention, various modification and ramifications of theforgoing embodiment are available. For example, a name resolutionexecuting means can be received through a network. An extensible systemsuch as additional software for example plug-in software can be used.The content storing unit of the receiving apparatus is not limited to aninternal hardware unit of the receiving apparatus. Alternatively, astoring unit that is accessible through an intra network can be used. Inaddition, as a network that has contents, other than the forgoingstructure can be used. In addition, the present invention is not limitedto content identifiers described in URI/URL. Other than identifiersdescribed in URI/URL can be used.

According to the present invention, the content name resolving means ofthe receiving apparatus unifies content name resolving processes onvarious networks. Thus, by inputting an identifier of a content that hasbeen unified regardless of the location thereof, the user can acquirethe content. As a result, the operability of the receiving apparatus canbe improved. In addition, according to the present invention, since aname resolution table that is transmitted from a broadcasting stationand an external name resolution table can be referenced, a new nameresolving means can be easily extensibly used.

1. A receiving apparatus for receiving data from a plurality ofdifferent communication networks as a content to be provided,comprising: multi-cast receiving means for receiving data from amulti-cast network; bi-directional receiving means for receiving datafrom a bi-directional network; content storing means for storing data asa content received by the receiving means; identifier identifying meansfor identifying an identifier of a desired content; name resolving meansfor interpreting the identified identifier and identifying a physicallocation of the content, said physical location being the multi-castnetwork, the bi-directional network and the content stonng means;content acquiring means for acquiring a content from the physicallocation identified by the name resolving means; means for causing thecontent acquiring means to acquire a content; and reproducing means forreproducing a content acquired by the content acquiring means, whereinsaid name resolving means executing a plurality of different nameresolving protocols by a first resolving means, which communicates withan external name resolving system for content located on the Internetthrough said bi-directional network and performs name resolution, asecond resolving means, which references a name resolution table fordigital stream broadcast network transmitted through said multi-castnetwork and performs name resolution, and a third resolving means, whichcorrelates the identifiers of the contents with the contents stored inthe content storing means.
 2. The receiving apparatus as set forth inclaim 1, wherein the name resolving means are disposed corresponding toname systems established by name managing organizations.
 3. Thereceiving apparatus as set forth in claim 1, wherein the name resolvingmeans is extensibly received through a network.
 4. The receivingapparatus according to claim 1, wherein the received data includesinformation about the content received by the receiving means.
 5. Thereceiving apparatus according to claim 1, wherein the received dataincludes content location information.
 6. The receiving apparatusaccording to claim 1, wherein the external name resolving system is adomain name system.
 7. The receiving apparatus according to claim 1,wherein the name resolution table is broadcast along with the contents.8. The receiving apparatus according to claim 1, wherein the thirdresolving means references a correlation table that correlates theidentifiers of the contents with file names in the content storingmeans.
 9. A receiving method for receiving data from a plurality ofdifferent communication networks as a content to be provided, comprisingthe steps of: receiving content data from a multi-cast network;receiving content data from a bi-directional network; storing thereceived content data from the multi-cast network and the bi-directional network; identifying an identifier of a desired content;resolving a name location of the received content data by interpretingthe identified identifier and identifying a physical location of thecontent, said physical location being the multi-cast network, the bi-directional network and a content storage of a receiving apparatus;acquiring a content from the physical location identified at theresolving step; and reproducing the acquired content, wherein resolvinga physical location by executing a plurality of different name resolvingprotocols including the steps of communicating with an external nameresolving system for content located on the Internet through saidbi-directional network, referring to a name resolution table for adigital stream broadcast network, transmitted through said multi-castnetwork, and correlating the identifiers of the contents with thecontents stored in the content storage.
 10. The receiving method as setforth in claim 9, wherein the name resolving step is performed for eachof name systems established by name managing organizations.
 11. Thereceiving method as set forth in claim 9, wherein the resolving step isextensible by additional software.
 12. The receiving apparatus accordingto claim 5, wherein the content location information insludes a filename of the contents, a network address of the contents, and informationthat designates a stream that is broadcast.